In August of 1999, NASA released an image of Cassiopeia A, a supernova remnant revealed in never-before-seen X-ray detail. The "Cas A" image, as it has come to be
known, shows remarkable structure in the debris of a
gigantic stellar explosion, as well as an enigmatic
source in the center, which could be a rapidly spinning
neutron star or black hole. The Chandra X-ray
Observatory image of Cas A ushered in a new era of
X-ray astronomy. This image was produced from the
archives to celebrate the anniversary of
Chandra’s first light. The low, medium, and
higher X-ray energies of the Chandra data are shown as
red, green, and blue respectively.